Acute Onset Ocular Hypotony after Coronary Artery Bypass Surgery

Abstract

Importance: The purpose of this case report is to evaluate risk factors associated with post-coronary artery bypass graft (CABG) ocular hypotony compared to post-CABG ischemic optic neuropathy. Observations: The patient described here is a single case at the University of California, Irvine Medical Center, from July 2016. This case demonstrates the rare incidence of acute post-CABG ocular hypotony and vision loss in a patient with prior history of optic atrophy. Both vision loss and hypotony resolved completely to baseline without intervention within 3 days postoperatively. Conclusions and Relevance: Severe anemia and large fluctuations in central venous pressure and blood pressure can occur in any patient undergoing CABG surgery. These hemodynamic shifts can cause transient ischemia to pressure controlling systems such as the ciliary body and reduce episcleral venous pressure. Other risk factors for acute hypotony in the setting of CABG surgery also include the use of hypertonic agents, cardiopulmonary bypass, and intravenous anesthesia.

Incidence and Risk Factors for Postoperative Visual Loss after Cardiac Surgical Procedures: A Systematic Review

“…This suggests that any medication with the potential to lower IOP can disrupt homeostasis in an already compromised setting. [ 14 ] Once the patient’s systemic blood pressure and arterial blood gases were normalized, the ocular hypotony resolved by postoperative day 1, eliminating the need for further treatment.…”

“…Clinically significant bilateral ocular hypotony can occur after CABG. [ 14 ] The mechanism of lowering of intraocular pressure is likely multifactorial, which includes large fluctuations in systemic blood pressure and partial pressure of oxygen, the administration of hyperosmotic agents and intravenous anesthesia, and CPB itself. This patient had spontaneous recovery of lost vision after 3 days of surgery.…”

Reporting A Case of Spontaneous Ocular Hypotony After the Neurosurgical ProcedureReporting A Case of Spontaneous Ocular Hypotony After the Neurosurgical Procedure

“…Among previously reported cases in non-ocular surgeries causing globe collapse, the most common were CABG and hypothermic cardiopulmonary bypass. In addition to hyperosmolar drugs like mannitol and sodium bicarbonate, the mean arterial pressure and CVP were also lowered; all these factors contributed to ocular hypotony (6,7).…”